This application is the national phase under 35 U.S.C. xc2xa7 371 of PCT International Application No. PCT/JP97/03537 which has an International filing date of Oct. 1, 1997, which designated the United States of America.
The present invention relates to a technique to uniformly affix a functional film on a panel of a cathode-ray tube and the like, whose surface has a curvature in three dimensional directions. The present invention covers the panel provided by using this technique and method and apparatus for fabricating the panel. It is natural that the present invention may be applied to a case where the functional film is affixed to a panel surface having the curvature in two dimensional directions.
There is a case where a functional film is affixed to a surface of a panel presenting an image in a fabrication process of a cathode-ray tube, for example, or other display devices. That""s because the functional film has an antistatic effect, a transmittance-support effect, an antireflection effect and the like.
There are two broad methods to affix the functional film on the panel surface of the cathode-ray tube.
The first method is, as shown in FIG. 33, using an ultraviolet hardening-type resin 2D to bond a functional film 2 to a surface of a panel 1A of a cathode-ray tube 1. In this method, the ultraviolet hardening-type resin 2D is applied to the surface of the panel 1A of the cathode-ray tube 1, and then the functional film 2 is put thereon and temporally affixed by pushing pressure of a roller 3P. After temporally affixing the functional film 2, the cathode-ray tube 1 is put into an ultraviolet irradiation furnace not shown, where the ultraviolet hardening-type resin 2D is harden under ultraviolet irradiation, to bond the functional film 2 to the surface of the panel 1A.
The second method is, as shown in FIG. 34, using the functional film 2 with an adhesive 2A on its one side to bond the functional film 2 on the surface of the panel 1A of the cathode-ray tube 1 by pushing pressure of the roller 3P. In this method, a release paper 2B (see FIG. 35) covering a surface of the adhesive 2A on one side of the functional film 2 is removed before the functional film 2 is put on the surface of the panel 1A of the cathode-ray tube 1 and the roller 3P travels in a travelling direction while applying pressure to the functional film 2, to bond the functional film 2. In this case, a film with hard-coat layer 2E formed on its one side surface, such as a polyethylene terephthalate (PET) film, is used as the functional film 2 as shown in the cross section of FIG. 35.
In both the above two methods, a mechanism is provided, by which the pressure of the roller 3P can be made almost uniform along the curvature of the surface of the panel 1A in the roller travelling direction. For example, a biaxial interpolation mechanism having a curvature approximate to that relative to the roller travelling direction of the surface of the panel 1A is fixed in a roller vertical direction and a roller travelling direction, to make the roller pressure uniform in response to the vertical variation of the panel surface. When a cylinder is used to generate a pushing force of the roller, a precision regulator for controlling the pressure is attached to the roller, to make the roller pressure uniform in response to the vertical variation of the panel surface. Further, if it is needed to control the pushing pressure to keep uniform with high precision, both the above biaxial interpolation mechanism for the roller vertical direction and the roller travelling direction and the precision regulator for controlling the pressure are used.
A problem common to the above two methods arises when the panel surface has a curvature in three dimensional directions, for example, in the cathode-ray tube.
For example, if the panel surface has such a shape as shown in FIG. 36, specifically, has a predetermined curvature in the XZ plane and a rectangular section in the YZ plane (defined as xe2x80x9ca panel surface having a curvature in two directionsxe2x80x9d), it is possible to affix the functional film on the panel surface almost completely uniformly with the pressure of the roller having the above biaxial interpolation mechanism.
However, if the panel surface has such a spherical shape as shown in Fig. (a) and (b) of 37 (defined as xe2x80x9ca panel surface having a curvature in three directionsxe2x80x9d), specifically, has curvatures both in the XZ plane and the YZ plane, when the functional film is pushed against the panel surface with the pushing roller 3P having a length l as shown in (b) of FIG. 37, the highest pressure is applied at a top portion TOP of the panel surface in the Z direction, causing large variation in thickness of the roller 3P, and on the other hand the variation in thickness of the roller 3P decreases towards end portions EP1 and EP2 and the lowest pressure is applied at both the end portions.
In this case, if the roller pressure at the end portions EP1 and EP2 is increased in order to improve the method of affixing the functional film at the end portions EP1 and EP2, the pressure applied at the top portion TOP becomes so high that it causes a damage to the panel surface. Therefore, the problem can not be solved by simply increasing the roller pressure.
Thus, in the method using the background-art tubular pushing roller, even if the mechanism that controls the roller pressure to be uniform along the curvature in the roller travelling direction is provided, there is a difference in pushing pressure at both the end portion sides of the panel surface in a plane perpendicular to the roller travelling direction, and that causes a problem that the functional film can not be affixed uniformly.
For example, in the method of bonding the functional film by using the ultraviolet hardening-type resin (hereinafter, referred to as xe2x80x9cultraviolet hardening-type resin bonding methodxe2x80x9d), since the panel of the cathode-ray tube has a complicate curvature in three dimensional directions, there is height difference in the vertical direction (the Z direction of FIG. 37) between the top position and the bottom position by several mm at both the end portion sides of the panel surface in the plane perpendicular to the roller travelling direction, to cause a large difference in roller pressure between the end portions. As a result, the ultraviolet hardening-type resin has a difference in thickness at both the end portion sides and air bubbles are likely to remain. Therefore, it is hard to affix the functional film uniformly with high quality.
Next, also in the method of bonding the functional film by using the adhesive (hereinafter, referred to as xe2x80x9cadhesive bonding methodxe2x80x9d), the same problem as in the ultraviolet hardening-type resin bonding method is manifested. Specifically, if the panel surface of the cathode-ray tube has a curvature in three dimensional directions, there is a large difference in roller pressure between the top portion and the end portion sides of the panel surface in the plane perpendicular to the roller travelling direction. As a result, the functional film is not sufficiently bonded and air bubbles are left in a surface to which weak pressure is applied, and that makes it extremely difficult to uniformly affix the functional film.
In this respect, as background arts intended to affix the functional film on the panel surface, there are inventions disclosed in Japanese Patent Application Laid Open Gazettes 7-326289 and 7-45186. These inventions, however, do not recognize the above problem at all nor present any means to solve the above problem. Therefore, it is impossible to adopt the techniques of these inventions.
The above problem is not confined to the panel of the cathode-ray tube, but necessarily arises in affixing the functional film on the panel surface having a curvature in three dimensional directions. For example, similar problem may arise in affixing the functional film on a panel surface of a window glass of an automobile. Therefore, suggestion on a new technique to solve the above problem and achieve fabrication of a panel with excellent functional film is strongly required.
The present invention is intended to solve the above problems and a main object of the present invention is to provide a panel in which a functional film is uniformly affixed on its surface having a curvature in three dimensional directions to take full advantage of the inherent function of the functional film, and to provide an apparatus for fabricating the panel and a method for fabricating the panel using the apparatus.
In the present invention, broad three methods as below are adopted to solve the problem.
(i) First, the present invention pays attention to always making a roller pressure uniform on a panel surface in a section cut from its front surface side by a plane perpendicular to the roller travelling direction.
(ii) Secondly, the present invention is grounded on a technical concept that the roller travels along the roller travelling direction to affix the functional film on the panel and immediately after the travel of the roller, another follow-up roller applies pressure locally to the functional film on both or either of the end portion sides of the panel surface intersecting the plane perpendicular to the roller travelling direction.
(iii) Finally, the present invention is grounded on applying the first technical concept to the second technical concept.
The above second and third technical concepts can be implemented with the following first to fifteenth aspects of the present invention. The aspects, and their actions and effects will be discussed below.
(1) According to a first aspect of the present invention, an apparatus for fabricating a panel with a functional film affixed on a surface thereof through a bonding source, comprises: a main pushing roller unit, of which a roller travelling direction is a first direction and a longitudinal direction is a second direction in a plane perpendicular to the first direction, being capable of pushing the functional film against the surface of the panel through the bonding source across the surface of the panel from a first end portion to a second end portion opposite to the first end portion both of which intersect the second direction and travelling along the roller travelling direction; and a first follow-up displacement pushing roller unit, of which a longitudinal direction is in parallel with the second direction and which is positioned on the side of the first end portion behind the main pushing roller unit relative to the roller travelling direction, being capable of pushing the functional film against the surface of the panel through the bonding source in a range of a first distance from the first end portion towards the second end portion and travelling along the roller travelling direction, wherein the first distance is smaller than a length of a side of the panel, the side of the panel connecting the first end portion to the second end portion in parallel with the second direction, and the main pushing roller unit is capable of travelling along the roller travelling direction, followed by the first follow-up displacement pushing roller unit in response to each other.
In the apparatus of the first aspect, the main pushing roller unit pushes the functional film against the panel surface within the range across the surface from the first end portion to the second end portion. In this case, when the panel surface has the curvature in three dimensional directions, as discussed above, there arises a difference in roller pressure at both of the first and second end portions of the panel surface or either (for example, the first end portion), and that causes a difference in thickness of the bonding source and the strength to bond the functional film is degraded at some portion or the functional film is not bonded at some portion.
In the apparatus, however, the functional film on the first end portion side is pushed by the main pushing roller unit and then is locally subjected to the pressure of the first follow-up displacement pushing roller unit which follows the main pushing roller unit, and that amends degradation in bonding strength of the functional film along the first end portion to make the thickness of the bonding source uniform. Moreover, an effect that the air bubbles are readily removed from the first end portion is achieved. Therefore, it becomes possible to affix the functional film uniformly with high quality on the panel surface.
For example, if a curved shape of the panel surface is problematic only on the side of the first end portion, the fabrication apparatus of the first aspect achieves the panel on which the functional film is affixed more uniformly with higher quality.
Further, if the curvature of the panel surface is problematic on both the sides of the first and second end portions, the functional film is affixed by using the apparatus of the first aspect and then further pushed by the apparatus of the first aspect travelling in a next roller travelling direction opposite to the initial roller travelling direction, to achieve the panel on which the functional film is affixed more uniformly with higher quality.
(2) According to a second aspect of the present invention, the apparatus for fabricating a panel with functional film of the first aspect further comprises: a second follow-up displacement pushing roller unit, of which a longitudinal direction is in parallel with the second direction and which is positioned on the side of the second end portion behind the main pushing roller unit relative to the roller travelling direction, being capable of pushing the functional film against the surface of the panel through the bonding source in a range of a second distance from the second end portion towards the first end portion and travelling along the roller travelling direction, wherein the second distance is smaller than the length of the side of the panel, and the main pushing roller unit is capable of travelling along the roller travelling direction, followed by the first follow-up displacement pushing roller unit and the second follow-up displacement pushing roller unit in response to one another.
In the apparatus of the second aspect, the functional film at the second end portion which is first pushed by the main pushing roller unit is subjected to the pressure of the second follow-up displacement pushing roller unit which follows the main pushing roller unit, and that amends incomplete bonding and degradation in bonding strength of the functional film which occur locally at the first and second end portions when the panel surface has the curvature in the three dimensional directions, to make the thickness of the bonding source uniform on the sides of both the end portions and remarkably reduce the air bubbles which are left. As a result, the functional film can be affixed more uniformly at the first and second end portions of the panel surface, and the inherent function of the functional film is achieved with high quality.
(3) According to a third aspect of the present invention, in the apparatus for fabricating a panel with functional film of the second aspect, the first follow-up displacement pushing roller unit comprises a first elastic roller capable of pushing the functional film directly against the surface of the panel; and a first equalizer changing an inclination of a center axis of the first elastic roller according to variation of a curvature of the surface of the panel along the roller travelling direction at the first end portion in a sectional plane defined by the second direction and a third direction perpendicular to the first and second directions, to thereby control the center axis of the first elastic roller to be in parallel with a first tangent direction in the sectional plane at the first end portion of the surface of the panel.
In the apparatus of the third aspect, the curvature of the first end portion of the panel surface in the section defined by the second and third directions varies along the first direction. At this time, the first equalizer is displaced according to variation of the above curvature to change the inclination of the center axis of the first elastic roller, thereby keeping on determining the inclination of the center axis of the first elastic roller along the roller travelling direction so that the center axis may be always in parallel with the first tangent direction. Thus, since the first follow-up displacement pushing roller unit travels and applies pressure on the side of the first end portion in the roller travelling direction while setting the inclination of the first elastic roller at the optimum value according to the curvature of the first end portion at times, it becomes possible to affix the functional film which can not be affixed by the pressure of the main pushing roller unit on the panel surface on the side of the first end portion, without air bubbles left, almost completely uniformly along the roller travelling direction.
(4) According to a fourth aspect of the present invention, in the apparatus for fabricating a panel with functional film of the third aspect, the second follow-up displacement pushing roller unit comprises a second elastic roller capable of pushing the functional film directly against the surface of the panel; and a second equalizer changing an inclination of a center axis of the second elastic roller according to variation of a curvature of the surface of the panel along the roller travelling direction at the second end portion in the sectional plane, to thereby control the center axis of the second elastic roller to be in parallel with a second tangent direction in the sectional plane at the second end portion of the surface of the panel.
In the apparatus of the fourth aspect, the second equalizer is displaced according to variation of the above curvature to change the inclination of the center axis of the second elastic roller, thereby keeping on determining the inclination of the center axis of the second elastic roller along the roller travelling direction so that the center axis may be always in parallel with the second tangent direction. Thus, since the second follow-up displacement pushing roller unit travels and applies pressure on the side of the second end portion in the roller travelling direction while setting the inclination of the second elastic roller at the optimum value according to the curvature of the second end portion at times, it becomes possible to affix the functional film which can not be affixed by the pressure of the main pushing roller unit on the panel surface on the side of the second end portion, without air bubbles left, almost completely uniformly along the roller travelling direction.
(5) According to a fifth aspect of the present invention, in the apparatus for fabricating a panel with functional film of the fourth aspect, the main pushing roller unit comprises a main elastic roller capable of pushing the functional film directly against the surface of the panel; and a main pressure control mechanism capable of controlling a main pressure independently, the first follow-up displacement pushing roller unit further comprises a first pressure control mechanism capable of controlling a first follow-up displacement pressure independently, and the second follow-up displacement pushing roller unit further comprises a second pressure control mechanism capable of controlling a second follow-up displacement pressure independently.
In the apparatus of the fifth aspect, since the pressure control mechanisms capable of controlling the pressures independently are provided for the respective rollers, it is possible to make the pressure almost uniformly against the functional film on the whole surface of the panel and moreover take advantage of the functions of the first and second equalizers in more optimum manner, and as a result, the panel can be provided, on which the functional film is affixed extremely uniformly with so high quality as takes full advantage of its inherent function.
(6) According to a sixth aspect of the present invention, in the apparatus for fabricating a panel with functional film of the fifth aspect, the main elastic roller comprises a center hole therethrough, the main pushing roller unit further comprises a shaft inserted into the center hole; an elastic roller holding part supporting both end portions of the shaft extending off the center hole; and a main pushing part connected to the main elastic roller holding part and the main pressure control mechanism, said main pushing part propagating the main pressure controlled by the main pressure control mechanism to the main elastic roller holding part, and wherein a clearance is provided between an outer surface of a portion of inserted part of the shaft in the center hole and a wall surface of the center hole.
There is a difference in height between the top portion and the first and second end portions (bottom portions) of the panel surface in the sectional plane defined by the second and third directions, perpendicular to the roller travelling direction. Therefore, the background art has a problem that there arises a difference in pressure between the top portion and the bottom portions and disadvantageously the pressures on the bottom portion sides anyway becomes lower.
In the apparatus of the sixth aspect, however, since the clearance is provided inside the main elastic roller, the pushing portion of the main elastic roller is displaced towards the hollow portion side of the clearance when the main elastic roller pushes the functional film against the panel surface. The displacement at the top portion is the maximum and that at the bottom portion side is the minimum. As a result, the thickness of the pushing portion of the main elastic roller becomes almost uniform in the plane defined by the second and third directions, the pressure of the main elastic roller is made uniform in the plane and the functional film can be affixed on the panel surface much more uniformly. At this time, few air bubbles are left and the functional film with high quality is achieved.
(7) According to a seventh aspect of the present invention, in the apparatus for fabricating a panel with functional film of the sixth aspect, the first elastic roller comprises a first center hole therethrough, the first follow-up displacement pushing roller unit further comprises a first shaft inserted into the first center hole; a first elastic roller holding part comprising the first equalizer, the first elastic roller holding part supporting both end portions of the first shaft extending off the first center hole; and a first pushing part connected to the first equalizer of the first elastic roller holding part and the first pressure control mechanism, the first pushing part propagating the first follow-up displacement pressure controlled by the first pressure control mechanism to the first elastic roller holding part, a first clearance is provided between an outer surface of a portion of inserted part of the first shaft in the first center hole and a wall surface of the first center hole, the second elastic roller comprises a second center hole therethrough, the second follow-up displacement pushing roller unit further comprises a second shaft inserted into the second center hole; a second elastic roller holding part comprising the second equalizer, the second elastic roller holding part supporting both end portions of the second shaft extending off the second center hole; and a second pushing part connected to the second equalizer of the second elastic roller holding part and the second pressure control mechanism, the second pushing part propagating the second follow-up displacement pressure controlled by the second pressure control mechanism to the second elastic roller holding part, and a second clearance is provided between an outer surface of a portion of inserted part of the second shaft in the second center hole and a wall surface of the second center hole.
In the apparatus of the seventh aspect, the pushing portion of the first elastic roller is displaced towards the hollow portion side of the above clearance when the first elastic roller pushes the functional film against the panel surface. The displacement at the top portion is the maximum and that at the bottom portion side is the minimum. As a result, the thickness of the pushing portion of the first elastic roller becomes almost uniform in the plane defined by the second and third directions, the pressure of the first elastic roller is made uniform in the plane and the functional film can be affixed on the panel surface much more uniformly.
Moreover, in the apparatus of the seventh aspect, the pushing portion of the second elastic roller is displaced towards the hollow portion side of the clearance when the second elastic roller pushes the functional film against the panel surface. The displacement at the top portion is the maximum and that at the bottom portion side is the minimum. As a result, the thickness of the pushing portion of the second elastic roller also becomes almost uniform in the plane defined by the second and third directions, the pressure of the second elastic roller is made uniform in the plane and the functional film can be affixed on the panel surface much more uniformly.
It is thereby possible to provide the panel having the functional film which is affixed almost completely uniformly on the whole panel surface and can fully perform its inherent function.
(8) According to an eighth aspect of the present invention, a method for fabricating the panel with the functional film through the bonding source by using the apparatus of the first aspect, comprises: a first step of disposing the panel, the functional film with its affixing surface facing the surface of the panel, the main pushing roller unit and the first follow-up displacement pushing roller unit positioned on the side of the first end portion behind the main pushing roller unit relative to the roller travelling direction at their predetermined positions; and a second step of controlling travel of the main pushing roller unit and the first follow-up displacement pushing roller unit in the roller travelling direction so that the main pushing roller unit travels, followed by the first follow-up displacement pushing roller unit, and both the main pushing roller unit and the first follow-up displacement pushing roller unit push the functional film against the surface of the panel through the bonding source, to affix the functional film on the surface of the panel with respective pressures of the main pushing roller unit and the first follow-up displacement pushing roller unit.
The eighth aspect of the present invention produces the same effect as the first aspect.
(9) According to a ninth aspect of the present invention, in the method for fabricating a panel with functional film of the eighth aspect, the first step comprises the step of further disposing the second follow-up displacement pushing roller unit, of which a longitudinal direction is in parallel with the second direction and which is positioned on the side of the second end portion behind the main pushing roller unit relative to the roller travelling direction, being capable of travelling along the roller travelling direction while pushing the functional film against the surface of the panel through the bonding source in a range of the second distance from the second end portion towards the first end portion in the second direction, and the second step corresponds to the step of controlling travel of the main pushing roller unit, the first follow-up displacement pushing roller unit and the second follow-up displacement pushing roller unit in the roller travelling direction so that the main pushing roller unit travels, followed by both the first follow-up displacement pushing roller unit and the second follow-up displacement pushing roller unit, and all of the main pushing roller unit, the first follow-up displacement pushing roller unit and the second follow-up displacement pushing roller unit push the functional film against the surface of the panel through the bonding source, to affix the functional film on the surface of the panel with respective pressures of the main pushing roller unit, the first follow-up displacement pushing roller unit and the second follow-up displacement pushing roller unit.
The ninth aspect of the present invention produces the same effect as the second aspect.
(10) According to a tenth aspect of the present invention, in the method for fabricating a panel with functional film of the ninth aspect, the first follow-up displacement pushing roller unit comprises a first elastic roller capable of pushing the functional film directly against the surface of the panel; and a first equalizer changing an inclination of a center axis of the first elastic roller according to variation of a curvature of the surface of the panel along the roller travelling direction at the first end portion in a sectional plane defined by the second direction and a third direction perpendicular to the first and second directions, to thereby control the center axis of the first elastic roller to be in parallel with a first tangent direction in the sectional plane at the first end portion of the surface of the panel, and the second follow-up displacement pushing roller unit comprises a second elastic roller capable of pushing the functional film directly against the surface of the panel; and a second equalizer changing an inclination of a center axis of the second elastic roller according to variation of a curvature of the surface of the panel along the roller travelling direction at the second end portion in the sectional plane, to thereby control the center axis of the second elastic roller to be in parallel with a second tangent direction in the sectional plane at the second end portion of the surface of the panel.
The tenth aspect of the present invention produces the same effect as the fourth aspect.
(11) According to an eleventh aspect of the present invention, in the method for fabricating a panel with functional film of the tenth aspect, the travel of the main pushing roller unit, the first follow-up displacement pushing roller unit and the second follow-up displacement pushing roller unit along the roller travelling direction is controlled while the respective pressures of the main pushing roller unit, the first follow-up displacement pushing roller unit and the second follow-up displacement pushing roller unit are controlled independently.
The eleventh aspect of the present invention produces the same effect as the fifth aspect.
(12) According to a twelfth aspect of the present invention, in the method for fabricating a panel with functional film of the eleventh aspect, the main pushing roller unit comprises a main elastic roller comprising a center hole therethrough; a shaft inserted into the center hole; an elastic roller holding part supporting both end portions of the shaft extending off the center hole; and a main pushing part connected to the main elastic roller holding part, the main pushing part propagating the pressure for the main pushing roller unit which is controlled to the main elastic roller holding part, a clearance is provided between an outer surface of a portion of inserted part of the shaft in the center hole and a wall surface of the center hole, the first follow-up displacement pushing roller unit comprises a first elastic roller comprising a first center hole therethrough; a first shaft inserted into the first center hole; a first elastic roller holding part comprising the first equalizer, the first elastic roller holding part supporting both end portions of the first shaft extending off the first center hole; and a first pushing part connected to the first equalizer of the first elastic roller holding part, propagating the pressure for the first follow-up displacement pushing roller unit which is controlled to the first elastic roller holding part, a first clearance is provided between an outer surface of a portion of inserted part of the first shaft in the first center hole and a wall surface of the first center hole, the second follow-up displacement pushing roller unit comprises the second elastic roller comprising a second center hole therethrough; a second shaft inserted into the second center hole; a second elastic roller holding part comprising the second equalizer, and supporting both end portions of the second shaft extending off the second center hole; and a second pushing part connected to the second equalizer of the second elastic roller holding part, propagating the pressure for the second follow-up displacement pushing roller unit which is controlled to the second elastic roller holding part, and a second clearance is provided between an outer surface of a portion of inserted part of the second shaft in the second center hole and a wall surface of the second center hole.
The twelfth aspect of the present invention produces the same effect as the seventh aspect.
(13) According to a thirteenth aspect of the present invention, a panel comprises: the surface on which the functional film is affixed by the method of the ninth aspect.
In the method of the thirteenth aspect, it is possible to provide the panel having the functional film which is affixed in an improved manner on the sides of the first and second end portions of the panel surface.
(14) According to a fourteenth aspect of the present invention, in the panel of the thirteenth aspect, the first follow-up displacement pushing roller unit comprises a first elastic roller capable of pushing the functional film directly against the surface of the panel; and a first equalizer changing an inclination of a center axis of the first elastic roller according to variation of a curvature of the surface of the panel along the roller travelling direction at the first end portion in a sectional plane defined by the second direction and a third direction perpendicular to the first and second directions, to thereby control the center axis of the first elastic roller to be in parallel with a first tangent direction in the sectional plane at the first end portion of the surface of the panel, and the second follow-up displacement pushing roller unit comprises a second elastic roller capable of pushing the functional film directly against the surface of the panel; and a second equalizer changing an inclination of a center axis of the second elastic roller according to variation of a curvature of the surface of the panel along the roller travelling direction at the second end portion in the sectional plane, to thereby control the center axis of the second elastic roller to be in parallel with a second tangent direction in the sectional plane at the second end portion of the surface of the panel, wherein the first follow-up displacement pushing roller unit comprising the first equalizer and the second follow-up displacement pushing roller unit comprising the second equalizer are moved in the roller travelling direction in response to the main pushing roller unit to affix the functional film on the surface.
In the method of the fourteenth aspect, it is possible to provide the panel in which the degradation in bonding strength of the functional film along the roller travelling direction at the end portions of the panel surface is remarkably amended.
(15) According to a fifteenth aspect of the present invention, in the panel of the fourteenth aspect, the travel of the main pushing roller unit, the first follow-up displacement pushing roller unit and the second follow-up displacement pushing roller unit along the roller travelling direction is controlled while the respective pressures of the main pushing roller unit, the first follow-up displacement pushing roller unit and the second follow-up displacement pushing roller unit are controlled independently, whereby the functional film is affixed on the surface.
In the method of the fifteenth aspect, it is possible to provide the panel having the functional film which is affixed extremely uniformly with high quality on the whole panel surface having the curvature in three dimensional directions.
The above first problem-solving method can be achieved by the sixteenth to twentieth aspects below. Constitutions, actions and effects in these aspects will be discussed below.
(16) According to a sixteenth aspect of the present invention, an apparatus for fabricating a panel with a functional film affixed on a surface thereof through a bonding source, comprises: a main pushing roller unit, of which a roller travelling direction is a first direction and a longitudinal direction is a second direction in a plane perpendicular to the first direction, being capable of pushing the functional film against the surface of the panel through the bonding source across the surface of the panel from a first end portion to a second end portion opposite to the first end portion both of which intersect the second direction and travelling along the roller travelling direction, wherein the main pushing roller unit comprises a main elastic roller comprising a center hole therethrough; a shaft inserted into the center hole; a main pushing part supporting both end portions of the shaft extending off the center hole; and a pushing part connected to the main elastic roller holding part, propagating a pressure for the main pushing roller unit to the main elastic roller holding part, and a clearance is provided at least between a wall surface of the center hole of the elastic roller on a side where the surface of the panel is pushed and an outer surface on the side where the surface of the panel is pushed of a portion of inserted part of the shaft in the center hole.
In the apparatus of the sixteenth aspect, the pushing surface of the elastic roller is displaced towards the side of the clearance according to the curvature of the panel surface in the plane perpendicular to the roller travelling direction. At this time, the displacement at the top portion is the maximum. Therefore, since the thickness and pressure of the elastic roller are made uniform on the whole surface of the panel in the plane, it is possible to improve the bonding state of the functional film at both the end portions.
(17) According to a seventeenth aspect of the present invention, in the apparatus for fabricating a panel with functional film of the sixteenth aspect, the inserted part of the shaft comprises a first portion having a first outer diameter corresponding to an inner diameter of the elastic roller; a second portion having a second outer diameter corresponding to the inner diameter of the elastic roller; and a third portion connected to the first and second portions and having an outer shape in which an outer diameter of any position is smaller than the inner diameter of the elastic roller.
The apparatus of the seventeenth aspect produces the effect of easily achieving the clearance by mechanical processing of the outer shape of the shaft.
(18) According to an eighteenth aspect of the present invention, in the apparatus for fabricating a panel with functional film of the seventeenth aspect, the outer shape of the third portion comprises a shape determined on the basis of a curvature of the surface of the panel in a sectional plane defined by the second direction and a third direction perpendicular to the first and second directions.
In the apparatus of the eighteenth aspect, since the pushing surface of the elastic roller can be deformed according to the curvature of the panel surface in the plane perpendicular to the roller travelling direction and the thickness of the elastic roller during pushing can be made almost even, it is possible to affix the functional film more uniformly.
(19) According to a nineteenth aspect of the present invention, in a method for fabricating a panel with functional film, the functional film is affixed on the surface of the panel through the bonding source by using the apparatus of the sixteenth aspect.
In the method of the nineteenth aspect, it is possible to affix the functional film by uniformly pushing against the whole panel surface in the plane perpendicular to the roller travelling direction.
(20) According to a twentieth aspect of the present invention, a panel comprises the surface on which the functional film is affixed by using the apparatus of the sixteenth aspect.
The panel of the twentieth aspect can have the functional film which is affixed uniformly with high quality on its whole surface.